Source: https://tctmed.com/low-t-info/what-is-low-testosterone/the-science-of-low-t-treatment/?__hstc=233546881.cb1a7a164018ba78c75a7905d3c4812c.1391453936462.1392927086781.1393353931781.8&__hssc=233546881.1.1393353931781&__hsfp=3931329112